DE3032558C2 - Logistic measuring device for clutches or brakes - Google Patents

Description

The invention relates to a measuring device according to the preamble of claim 1, with the help of which the different axial path measured and z. B. as a basis for setting a clutch or Brake is used. Such devices are available on both single-disc and multi-disc clutches and brakes known as hydromechanical position measuring devices and therefore highly tolerant and wear-dependent. They are used to precisely control a clutch or brake, especially if one defined pressure build-up or reduction is necessary, not suitable. Should they still be used, is a relatively large construction or control and maintenance effort required.

Such a distance measuring device is known from DE-PS 42 736. In this document the actuation a clutch used as a shift lock for a pressure medium-operated gearbox, in which travel-dependent A switching valve is used to shut off the pressure medium via a towing device.

Logistic measuring devices are known from the company brochures of AEG »Logistat« from and 1962, where z. B. the path or certain positions are converted into values without contact using slot initiators where the depth of immersion of a metal object in the slot is the magnetic field influenced and thereby a signal, z. B. to a functional member, delivers.

It is the object of the invention to provide a measuring device according to the preamble of claim 1, which Works independent of tolerances and wear as well as low construction, control and maintenance costs requires

This object is achieved with the characterizing features of claim 1

While with a hydraulic / mechanical distance measuring device the reference point for the beginning the control or regulating system for the pressurization or

ίο -dismantling of the clutch or brake taking into account of tolerances and a relatively significant amount of wear and tear must be set and thus only approximate values are achievable, it is possible to electrically point the point on the axial path from Pressure piston, when a full power transmission takes place in the clutch or brake, always anew so that any wear that occurs in a permissible range no longer has any influence on the control or Rule has

Will the: stored reference point according to claim 2 is used as the output point for the regulation or control system, it is only possible to use this system to be determined on the basis of the really necessary pressure build-up or decrease.

The path for the regulated or controlled pressure build-up or reduction can therefore be optimally determined and can also be set and is therefore a route without any change. The beginning of this tax or The controlled system only shifts in the same way as the reference point changes as a result of the meanwhile the wear and tear that has occurred

After the exact control or regulation point for the beginning of the pressure build-up or pressure reduction for each Actuation is newly and precisely determined, you can accelerate the clutch process without Concerns according to claim 3 put a rapid route in front of the control or regulation path, so that the result of z. B. Lamella wear ever longer distance between the starting point and the The application point of the clutch or brake is passed through quickly.

Furthermore, it is also possible according to claim 4, with a predetermined permissible wear of the To program a wear mark, so that a signal is triggered as soon as it affects the slats Wear mark covers the reference point to be moved with this.

Furthermore, it is also possible to approach this wear mark, as well as exceeding it, as

so to give information.

If the electrical variable, which is proportional to the path, is recorded via a secondary coil according to claim 5, the implementation of the encoder is particularly simple and insensitive.

Particularly great structural advantages and further simplifications arise if for the electrical detection of the path, the same principle is used as when determining the arrival or departure Output speed, as shown in FIG. 1 is shown.

In the following, further details of the invention are based on an exemplary embodiment and explained by drawings. It shows

F i g. 1 a half-section through a coupling with an electrical travel sensor,

F i g. 2 shows a schematic representation of the path of a pressure piston on a clutch,
F i g. 3 Circuit arrangement of the position measuring device.
In Fig. 1 is a clutch 1 with an outer disk

carrier 11 as a drive flange and outer disks 12 an inner disk carrier 13 as an output flange and inner disks 14 one between the outer disk carrier and the pressure piston 15 lying on the inner disk carrier to open and one with springs 17 Actuated actuating piston 16 arranged to close the clutch on actuating piston 16 a cup-shaped body 21 is attached to the clutch 1, which controls the axial movement of this actuating piston 16 participates, the axial support of the disk pack 12, 14 takes place on an end disk 18. The transmission from the pressure piston 15 to open the clutch 1 the side of the actuating piston 16 facing away from the springs 17 takes place via bolts 19.

A carrier 31 detachably connected to the housing 3 carries the primary coil 22 and the secondary coil 23, which together with the cup-shaped body 21 form the position transducer 2. The stationary primary 32 and secondary coils 33 for determining the output speed as well as the primary 35 and secondary coils 36 for the drive speed are also attached to or in the carrier 31 attached to the outer disk carrier 11 or to the inner disk carrier 13

In the state of the closed clutch 1 - as shown - the spring 17 presses the actuating piston 16 against the disk pack 12, 14, which is supported by the end disk 18. The pressure chamber 10 is vented, and the cup-shaped body 21 of the transducer 2 interrupts the homogeneous stray field between the primary and secondary coil only slightly, so that there is a relatively high voltage. The depth of immersion of the cup-shaped body 21 in the gap between the primary 22 and the secondary coil 23 when the clutch is closed must be such that at least the entire permissible wear on the clutch - on the lamellae - is taken into account, so that even if one is still permissiblely worn Coupling results in an increase in the voltage in the secondary coil

In the respective end position of the actuating piston - i.e. in this position, which corresponds to the full torque transmission - and also has the greatest voltage for this closing process, this electrical signal is recorded and stored and used as a reference point 40 for the subsequent defined clutch actuation. To open the clutch 1, the pressure chamber 10 is acted upon.The pressure piston 15 moves in the direction of the actuating piston 16 and pushes it back to the starting point 41 via the bolts 19 against the pressure of the spring 17 2 so that there is a lower voltage in the secondary coil.

From FIG. 2a shows the voltage U in the secondary coil, based on the travel of the actuating piston, with 21 '- FIG. 2b - corresponding to the position of the cup-shaped body 21 when the clutch is completely closed. With increasing wear, the cover of the primary coil decreases, so that the voltage increases in this closed position. 21 "represents a position that corresponds to the greatest permissible wear in the clutch. Position 2Γ" corresponds to the open clutch with the largest cover at the same time the secondary coil.

In FIG. 2c, the intended pressure profile is shown over the path. Points 400, 400 ' to 430 correspond to points 40, 40' to 43 from FIG. 2a.

If the clutch is to be closed, the pressure chamber 10 is partially vented. The relatively strongly compressed Springs 17 cause a rapid closing movement from the starting point 41 - that of the opened one Coupling corresponds to - up to application point 421 at which put on the slats and start a defined closing process. Venting now takes place

ίο regulated or controlled. At the reference point 40 'the clutch is closed again and transmits the full torque and this reference point 40', which deviates slightly from the previously stored reference point 40 - namely by the amount of wear in the clutch - is saved for a new actuation cycle the regulated or controlled venting from the application point 42, 42 'to the reference point 40, 40' is always constant, while the wear causes the rapid path 46 to be lengthened from the starting point 41 to the application point 42, 42 '. The reference point 40, 40 ′ moves from actuation to actuation of the clutch - even if these steps are very small - towards the wear mark 43. It is possible, by means of suitable programming, to show the approach to the intended wear mark, whether it has been reached or exceeded, by means of suitable displays or to pass on corresponding information.

In Fig. 3 shows the switching arrangement for the distance measuring device 2, the voltage U proportional to the distance being continuously output from any transducer 50 - e.g. B. as in FIG. 1 described - an analog-to-digital converter 51 is fed. A control signal from the controller, not shown, which corresponds to the reference point 40, 40 ' - F i g. 2a - is passed through a cut trigger 53 and pulse shortener 54 and fed to the first memory 52 and causes the storage of the travel marker - reference point 40, 40 '-, i.e. the point at which the clutch transmits the full torque - this reference point 40, 40 ' is at the same time the point with the highest voltage t / proportional to the path for each switching cycle. The two halves of the coupling, i.e. the input and output, also have the same speed at this reference point, so that this point can also be represented very easily.

When the clutch is opened, the pressure chamber 10 is acted upon - FIG. 1 - and, after it is fully opened, the controller outputs starting point 41, 410, FIG. 2 - a signa! to the second memory 55 for taking over the value held in the first memory 52, so that this first memory 52 is ready again for a further switching cycle for storing the reference point 40 '. The precise signal transmission is again ensured - as with the first memory 52 - by a cut trigger 53 'and a pulse shortener 54'. From the reference point 40, 40 ' for the completely closed clutch 1, newly determined for each switching cycle and stored in the second memory 55, and the distance 45 - F i g valid in the read-only memory 56 - PROM - for all cycles. 2a - and defined pressure curve between point 420 and 409 or 420 ' and 400' in FIG. 2c, a corresponding correction value is formed, converted again in a digital-to-analog converter 57 and fed as a manipulated variable or a correction to the manipulated variable to a control device - not shown.

By the arrangement z. B. another read-only memory 58, it is possible to mark a wear mark 43 - F i g. 2a - when it is reached, that is to say reference point 40 'meets point 43 of the wear mark, it is also possible to trigger a corresponding signal or a command. At the same time it is of course possible to indicate with each cycle whether the wear is still in the permissible range or the reference point 40 'is in the critical range or whether the wear mark has been exceeded, as can be seen from the illustration 59 in FIG. 3 emerges. The read-only memory 56 can be stored for a repeatable process according to the desired defined pressure build-up or pressure reduction and is continuously activated with the second memory 55 so that when the marker is reached - reference point 40 _s 40 'minus the regulated controlled route 45, i.e. at the landing point 42, which corresponds to the point of the applied lamellae - the defined application of the clutch 1 as a result of the pressure increase or decrease can begin.

It is also possible to activate the read-only memory 56 via the input 60. Next is that Read-only memory 56 can be exchanged quickly, so that several programs for closing / opening a Clutch / brake can be kept ready for different conditions.

Power is supplied via the power source 61 of the on-board network. To when changing this power source or to store the reference point 40, 40 'in the event of other failures, the second Memory 55 is equipped with its own battery 65 (NiCd rechargeable battery), which is fed via the charging resistor 62 from On-board network is charged. The power supply in the event of an on-board network failure takes place via the between the second memory 55 own battery 65 and the second memory 55 self-arranged second diode 64, while in normal operation the power supply to both the second memory 55 and the Charging resistor 62 takes place via the first diode 63. The charging voltage of the storage's own power source 65 must be well below the normal supply voltage of the power source 61 of the electrical system stand.

To avoid unwanted information during the »off« operation due to static Voltages must be the control input of the second memory 55 (from the regulator) with a resistor 66 loaded and connected to the power supply of the second memory 55.

The electrical detection of the reference point 40, 40 'in the position encoder 2 is not limited to that in the example and in the Figures shown limited way on the basis of an eddy current generator, but can also with

z. B. a differential transformer or short-circuit ring encoder take place.

Reference number

5 1 Clutch / brake 10 Printing room U Outer disk carrier as drive flange 12th Outer lamellas 13th Inner plate carrier as an output flange 10 14th Inner lamellas 15th Plunger 16 Actuating piston 17th feathers 18th End lamella 15th 19th bolt 2 Weggeber 21 Pot-shaped body 22nd Primary coil 20th 23 Secondary coil 3 casing 31 carrier 32 Primary coil 25th 33 Secondary coil 34 Curves or tooth lock washer 35 Primary coil 36 Secondary coil 37 Curves or tooth lock washer 30th 40 Reference point 41 starting point 42 Mooring point 43 Wear mark 45 Regulated / controlled route 35 46 Express route 50 Transmitter 51 Analog-to-digital converter 52 First store 40 53 Cut trigger 54 Pulse shortener 55 Second memory 56 Read-only memory 57 Digital-to-analog converter 45 58 Read-only memory 59 Information display 60 Command for read-only memory 61 Power source on-board network 62 resistance 50 63 diode 64 diode 65 Auxiliary battery 66 resistance

For this purpose 3 sheets of drawings

Claims (5)

Patent claims: 1. Logistic measuring device for clutches or brakes, characterized in that that for use in switching operations, the respective end position of the actuating piston (16), in which the maximum torque is transmitted, is generated and detected as a reference point (40). 2. Measuring device according to claim 1, characterized in that each stored Reference point (40) Basis is for a regulated or controlled pressure build-up / reduction between application (42) and end point (reference point 40) of the frictional engagement. 3. Measuring device according to one of the preceding claims, characterized in that each Stored reference point (40) is the basis for the location of a rapid route (46) between the starting point (41) and the application point (42) 4. Measuring device according to one of the preceding claims, characterized in that the reference point (40) interacts in connection with a programmed wear mark (43) which corresponds to a waypoint. 5. Measuring device according to one of the preceding claims, characterized in that the displacement encoder (2) a power source attached to the housing (3) and arranged in the axial direction connected primary coil (22), a secondary coil connected to the transducer (50) (23) and one arranged between the primary and secondary coil with the pressure piston (16) connected, axially movable, cup-shaped body (21) consists.